Tumblr, the world’s premiere blogging platform, is making the unprecedented move to ban adult content site-wide. In a statement today, the website declared that “Starting Dec 17, adult content will not be allowed on Tumblr, regardless of how old you are.” Clarifying what “adult content” encompassed, the company went on to say “Adult content primarily includes photos, videos, or GIFs that show real-life human genitals or female-presenting nipples, and any content—including photos, videos, GIFs and illustrations—that depicts sex acts.”

This move follows a series of controversies surrounding the website’s previous handling of pornographic content. The official Tumblr app was recently de-listed from the Apple App Store, which many believe was due to images of child sexual abuse that were present on the platform. In addition, blogs featuring adult content have been seeing their posts deleted by Tumblr administration, likely as an attempt by the company to distance itself from allegations of hosting unchecked child pornography.

Whatever the case, this latest development is certainly a bold move. The keyword “Tumblr” shot to the top of Twitter’s US trends; the vast majority of related tweets express disapproval for the move. The nature of Tumblr as a blogging platform makes it particularly popular for internet users to curate pornographic content to their liking. With this move, that is seemingly no longer possible.

There is still some uncertainty in this “total ban,” however. The statement clarifies: “Examples of exceptions [of adult content] that are still permitted are exposed female-presenting nipples in connection with breastfeeding, birth or after-birth moments, and health-related situations, such as post-mastectomy or gender confirmation surgery. Written content such as erotica, nudity related to political or newsworthy speech, and nudity found in art, such as sculptures and illustrations, are also stuff that can be freely posted on Tumblr.” This certainly leaves a grey area for content; how explicit can art be before it gets removed? Are photographs, as they are an artistic medium, allowed? Could you simply go to a pornographic website, take a screenshot of a scene you like, and post it on your blog?

We don’t know the answers to those questions. What we do know is that Tumblr will be under pressure from all angles following this decision. Users and press alike are already making their dissatisfaction known with this move; the company will certainly face a tough test in the following weeks. This article will be updated as Tumblr releases more information on this change.